In the Lucas electronics world, apparently. I recently mounted and wired up some aftermarket LED fog lights in place of my damaged and missing stock ones. To make things “easier” I soldered the fog light pigtail with the connector to the lights so I could just plug them right in. The moment of truth arrives, I push the fog light button on the dash, and nothing... After some investigation with the multimeter it turns out that the wires on the light (Brown and Black) are connected in such a way where the black wire connects to the positive side of the connector on the truck! Lucas, Prince of Darkness indeed...

Although the stock fog lights are made by Hella, so perhaps ze Germans are to blame.

 

Really old English cars used positive ground because their electricians were trained by physicists and electrons are negative. After a couple of old English sports cars I actually thought that was strangely logical, but it seems the entire world switched to do it like Americans, so electrons flow on the positive red wires and return to the battery on the negative black wires... because of course power is always positive, right?

And, yes, I'm American.

Joking aside, I've seen some really lazy wiring in cars over the years. My second car was a 1962 Volkswagen that had been partially rewired by a hippie in Alaska, and the only color of wire he had was red. My **** engineering mind caused me to buy lots of pretty colors of wire to rewire that whole car one summer. I think I still have some of the blue with green tracer out in the garage 30 years later.

Scott

 

I believe China uses a positive ground system.. Or at least they have a backwards concept of wire colors than we do because they work like normal black = +

 

This is most amusing, I agree. What's Lucas on the truck though?

 

In the Air Force we had a few negative ground heater and air compressor units that were British made.

 

I had an early 70s Fiat 124 that somebody in the past had used all purple wires to rewire the centre console. Unfortunately for me, one of the most important switches in the car in the console, the four way flasher switch.. If this switch is inoperative, you do not have turn signals. Trying to trace out all purple wiring in the middle of winter was maddening.

 

Lol. I don't do ANYTHING without my meter... then again I spend a lot of time working on Norwegian equipment... all gray... and bowl of spaghetti? Yes.

 

Just as a follow up, after reversing the electrical connection everything works! Interesting and humorous to commiserate with your (far worse) strifes of automotive wiring craziness.